Method of reenforcing porous paper



Nov. 10, 1931. E. F. WOODWARD 1,

METHOD OF REENFORCING POROUS PAPER I Filed May 2, 1930 INVENTOR v will)" Patented Nov. 10, 1931 UNITED STATES- PATENT o EDGAR r. woonwann. on

FF cE METHOD OF REENFORCING POROUS PAPER I Application filed May 2, 1930. Serial- No. 449,808

This invention relates to reenforced porous pa er and method of making same, and pro-- ,vi es a ters that is pervious to air and will retain dust and refuse. Other objects will appear from the specifications and drawings herewith.

To these ends the invention consists of the construction and arrangements of mechanism for the reenforcement of porous paper set 1 forth and illustrated in the. accompanying drawings in which: v 4 Y Fig. 1 is a. view in side elevation partly in section showing a mechanism employed in practicing my invention with the drivin mechanism such as motors, chains, belts'an gears eliminated to more clearly illustrate the operation. Fig. 2 is a side elevational .view, partly in section of a modified form of same and, Fig. 3 is an enlarged plan view of a modified form of the gummin roller.

Similarcharacters of reference enote like parts in the various figures.

Fig. 1 is a view partly in section, of an operating plant arranged to carry out'the" reenforcement method described in which A is a roll of clothlike material, such as cheesecloth, Bisa roll of porous paper, 2 and '3 are preferably rubber rollers between which the clothlike fabric is passed, 4 is a receppaper are respectively carried upon shafts 16 which 'will be retained by the fabric after passing between the rollers, The,lower or gumming roller 3, is partly submerged in the adhesive or gum and the upper roller 2 may be adjusted to squeeze the surplus gum,

. 2 and v 3. These mu cilage or other adhesive in solution out of the fabric. The fabric used must be of'loosecloth .or tobacco cloth, so that when attached .to the paper, after the surplus adhesive has I" been squeezed out, it will only close the pores BROOKLY NEW YORK, nssranon' 'ro LEWIS c. v nnnrrna.

' or BROOKLYN, New YORK ly woven netlike material such as cheesem the paper wherethe strands of cloth come into contact with said paper and the adhesive allowed to remain in the cloth will only be s'to of sufficient quantity to cause said stran become attached to the paper, .but not sufiicient tospread over. the paper where not in contact with the netlike strandsof fabric,

Thus the porosity ofthe' paper will not be entirely destroyed and infact almost any degree of porosity may be retained by using fabric of a larger mesh.

I The rollers 2a and 3a (Fig.1) are. also provided for the purpose of -further squeezing any surplus solution out'of the fabric and are arranged to be adjusted in relation to each other in a similar manner to'the rollers if desired.

Both the clothlike fabric and paper are" caused to move synchronously in the direction shown by the arrows 7-8andpass between the steel rollers 9 and 10 which are arranged to eizert comparatively great pressure porous paper A-B which is then run through an oven or othercom'partment upon rollers 1314; 15 and thoroughly dried.

The rolls of clothlike fabric and porous and 17 which in turn are provided with bearings and the rollers 9 and 10 are-preferably connected to driving means such as motor pow'er'to carry the paper and cloth-like fab-u ric through. Afterpassing through the oven rollers may be eliminated" in which 2021 are heating coils, or other hot air chamber, the reenforced porous paper I AB may be used inthe making of dust collectors, -dust bags or for any purposefor T shown in Fig. 3, wherein the gumming roller which a strong porous, inexpensive material is des red A modlfied form of thegumming roller is 06- is provided with projecting teeth or pins, separated from each other, so that the entire surface of the clothlike fabric is not coated with the adhesive, butonly dot, (19) dash shaped (19 or other shaped coatin s of gum are put on in predetermined space positions, thus leaving the spaces between the dots, dashes or other gummed designs free of gum or other adhesive.

In Fig. 2 I have shown a modified form of reenforcing plant in which the gumming roller 3 is arranged .to supply gum to a sup plemental gumming roller 1919 shown in Fig. 3 which in turn supplies gum to the fabric, but only in predetermined spaced positions, so that the entire surface of the fabric is not coated, but'portions are left free of the adhesive.

The method of attaching cloth to paper by means of an adhesive is not new, but heretofore it has been done 'only for the purpose of I strengthening paper for use in the arts and for wrapping etc., and by all the well known processes the adhesive used would close the pores in paperif it were of a porous nature such as I use in my present process. In no instance, so far as I am aware, has reenforced porous paper been prepared 1n such a way that it remained porous after being reenforced by a clothlike fabric until my invention thereof, and it is essential that it remain sufiiciently porous to allow air to pass through freely when used for a dust bag or filter adapted for use on pneumatic cleaners.

I claim:

1. The method of producing a reenforced porous paper, which comprises feeding from rolls sheets of porous paper and net-like fabric respectively, applying an adhesive to said fabric and removing excess adhesive, thereby leaving the meshes of the fabric free .of adhesive, pressing said fabric sheet into face contact with said porous paper and drying the unitary sheet, whereby the porosit' of said paper is substantially undiminishe 2. The method of reenforcing porouspaper which comprises feeding from rolls sheets of said porous paper and a net-like fabric respectively, passing said net-like fabric in contact with a rollercarrying an adhesive, then squeezing-said net-like fabric to remove surplus adhesive therefrom, so that said adhesive will not spread over saidp.0- rous paper between the strands of said netlike fabric, applying said fabric in face to face contact with said porous paper, and

' pressing same together, then drying the paper and fabric, whereby the porosity of said paper will be substantially undiminished.

' EDGAR F. WOODWARD. 

